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Abstract:

An electrostatic image-developing toner comprising a binder resin,
wherein the content of all the chlorine-substituted benzene derivatives
in the electrostatic image-developing toner is about 0.01 ppb or more and
about 10 ppb or less.

Claims:

1. An electrostatic image-developing toner comprising a binder resin,
wherein the content of all the chlorine-substituted benzene derivatives
in the electrostatic image-developing toner is about 0.01 ppb or more and
about 10 ppb or less.

2. An electrostatic image developer comprising the toner according to
claim 1 and a carrier.

3. A toner cartridge comprising the electrostatic image-developing toner
according to claim 1.

4. A process cartridge comprising: at least one selected from the group
consisting of: a latent image holding member, a charging unit for
charging the latent image holding member, an exposing unit for exposing
the charged latent image holding member to form an electrostatic latent
image on the latent image holding member, a developing unit for
developing the electrostatic latent image with the electrostatic image
developer according to claim 2 to form a toner image, a transfer unit for
transferring the toner image from the latent image holding member to a
transfer-receiving member, and a cleaning unit for removing the toner
remaining on the surface of the latent image holding member.

5. An image-forming method comprising: a charging process for charging a
photoreceptor, an exposing process for exposing the charged photoreceptor
to form a latent image on the photoreceptor, a developing process for
developing the latent image to form a developed image, a transfer process
for transferring the developed image to a transfer-receiving member, and
a fixing process for fixing the toner on a fixation base material by
heating, wherein the toner is the electrostatic image developing toner
according to claim 1.

6. An image-forming apparatus comprising: a latent image-forming unit for
forming a latent image on a latent image holding member, a developing
unit for developing the latent image with an electrostatic image
developer, a transfer unit for transferring the developed toner image to
a transfer-receiving member through or not through an intermediate
transfer member, and a fixing unit for fixing the toner image on the
transfer-receiving member, wherein the electrostatic image developer is
the electrostatic image developer according to claim 2.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on and claims priority under 35 USC 119
from Japanese Patent Application No. 2010-62246 filed on Mar. 18, 2010
and Japanese Patent Application No 2010-144526 filed on Jun. 25, 2010.

BACKGROUND

[0002] 1. Technical Field

[0003] The present invention relates to an electrostatic image-developing
toner, an electrostatic image developer, a toner cartridge, a process
cartridge, an image-forming method, and an image-forming apparatus.

[0004] 2. Related Art

[0005] Methods of visualizing image data via an electrostatic latent image
such as an electrophotographic method are now widely used in various
fields. In the electrophotographic method, an electrostatic latent image
formed on the surface of an electrophotographic photoreceptor (an
electrostatic latent image carrier, hereinafter sometimes referred to as
"a photoreceptor") is developed through a charging process and an
exposure process with an electrostatic image-developing toner
(hereinafter sometimes referred to as merely "a toner"), and the
electrostatic latent image is visualized through a transfer process, a
fixing process, and the like.

[0006] There is a high possibility that printed matters obtained by
fixation of images by an electrophotographic method and the like are
brought into contact with many and unspecified persons according to uses,
and with sanitation-oriented trend in recent years, a demand for printed
matters having an antibacterial effect has increased.

SUMMARY

[0007] According to an aspect of the invention, there is provided an
electrostatic image-developing toner comprising a binder resin, wherein
the content of all the chlorine-substituted benzene derivatives in the
electrostatic image-developing toner is about 0.01 ppb or more and about
10 ppb or less.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Exemplary embodiment(s) of the present invention will be described
in detail based on the following figures, wherein:

[0009]FIG. 1 is a schematic diagram showing an example of the
constitution of the image-forming apparatus for use in the image-forming
method in the invention,

[0012] The electrostatic image developing toner, electrostatic image
developer, image-forming method and image-forming apparatus in the
exemplary embodiment of the invention are described below.

[Electrostatic Image-Developing Toner]

[0013] The electrostatic image developing toner (hereinafter also referred
to as "the toner") in the exemplary embodiment contains at least a binder
resin, and the content of all the chlorine-substituted benzene
derivatives in the electrostatic image developing toner is 0.01 ppb or
more and 10 ppb or less or about 0.01 ppb or more and about 10 ppb or
less, and preferably 0.1 ppb or more and 3 ppb or less or about 0.1 ppb
or more and about 3 ppb or less. When the content of all the
chlorine-substituted benzene derivatives in the electrostatic image
developing toner is less than 0.01 ppb or less than about 0.01 ppb, not
only the addition becomes difficult in practice but also the
antibacterial action to a fixed image is low, and the antibacterial
action in every fixed image becomes uneven. On the other hand, when the
content of all the chlorine-substituted benzene derivatives in the
electrostatic image developing toner exceeds 10 ppb or exceeds about 10
ppb, there is a case where tone reproduction of a fixed image is marred
due to the electrical conductivity of all the chlorine-substituted
benzene derivatives in particular under a high temperature high humidity
condition.

[0014] The content of all the chlorine-substituted benzene derivatives in
the electrostatic image developing toner may be the amount contained in a
coloring agent, or the content may be decreased to the amount determined
in advance by washing etc. of a coloring agent, alternatively they may be
additionally blended with a toner pigment. More specifically, a method of
dispersing them in an organic solvent such as tetrahydrofuran or toluene,
stirring, filtering, and repeating the procedure several times, a method
of performing Soxhlet extraction of a pigment with the above solvent, and
a method of combining these methods are exemplified. All the
chlorine-substituted benzene derivatives are those obtained by
substituting benzenes with chlorine atoms. Specifically, the content of
all the chlorine-substituted benzene derivatives shows the total amount
of the chlorine-substituted benzenes such as monochlorobenzene,
dichlorobenzene, trichlorobenzene, etc., to the entire amount of the
toner.

[0016] Release agents for use in the toner of the exemplary embodiment are
preferably release agents having low compatibility with the binder resin,
for example, release agents of low polarity such as polyethylene,
polyolefin and the like from the point of obtaining a good peeling
property of a halftone image, and the melting temperature thereof is
preferably 100° C. or more in view of a good peeling property of
the toner from the paper and coming out of uneven gloss with difficulty.
Since it is necessary for release agents to enter between the fixing
member and the image within a short time, the above-exemplified release
agents are preferably used.

[0017] Further, each material constituting the toner in the exemplary
embodiment will be described below in detail.

[0020] Besides the above, various components such as internal additives,
charge controlling agent, inorganic powders (inorganic particles),
organic particles, and the like can be added to the toner according to
necessity. The examples of internal additives include magnetic powders,
for example, metals such as ferrite, magnetite, reduced iron, cobalt,
nickel, manganese, etc., alloys, and compounds containing these metals.
As charge controlling agents, for example, quaternary ammonium chloride
compounds, nigrosine-based compounds, dyes comprising aluminum, iron or
chromium complex, and triphenylmethane-based pigments are exemplified.
Further, inorganic powders are mainly added for the purpose of adjusting
a viscoelastic property of the toner, and all the inorganic particles
which are usually used as external additives of toner surfaces as
described in detail below, such as alumina, titania, calcium carbonate,
magnesium carbonate, calcium phosphate, cerium oxide, and the like are
exemplified.

[0021] The volume average particle size of the toner in the exemplary
embodiment is 3 μm to 10 μm, preferably 3 μm to 9 μm, and
more preferably 3 μm to 8 μm. The number average particle size of
the toner in the exemplary embodiment is preferably 3 μm to 10 μm
and more preferably 2 μm to 8 μm. When the particle size is too
small, sometimes not only productivity becomes unstable but also
chargeability is insufficient and developing property lowers, while when
the particle size is too large, the resolving property of an image
lowers.

[0022] As the manufacturing method of the toner in the exemplary
embodiment, for example, a kneading and pulverizing method of kneading
the above binder resin, coloring agent, and, if necessary, a release
agent, pulverizing and classifying, and a method of changing the shapes
of the particles obtained by the above kneading and pulverizing method by
mechanical impact force or heat energy are exemplified.

[0023] As the above kneading and pulverizing method, manufacture is
carried out, for example, as follows: In the first place, the components
such as the binder resin, coloring agent, infrared absorber, and the like
are mixed, and then kneaded by melting. As the melt-kneaders, three-roll
type, single screw type, double screw type and Banbury mixer type
kneaders are exemplified. The obtained kneaded product is roughly
pulverized, and then pulverized with a pulverizer, e.g., a micronizer, an
Urumax, a Jet-O-miter, a jet mill, a Krypton, or a turbo mill, and then
subjected to classifying treatment with a classifier, e.g., an Elbow-Jet,
a Micro-Plex, or a DS Separator, to thereby obtain a toner.

[Electrostatic Image Developer]

[0024] The toner to be obtained by the manufacturing method of the
electrostatic image developing toner in the exemplary embodiment is used
as an electrostatic image developer. The developer is not especially
restricted so long as it contains the electrostatic image developing
toner, and it can take arbitrary composition of components according to
purposes. The electrostatic developer may be prepared as one-component
type electrostatic image developer comprising the electrostatic image
developing toner alone, or may be prepared as two-component type
electrostatic image developer in combination with a carrier.

[0025] The carrier is not especially restricted and known carriers
themselves are exemplified. For example, known carriers such as
resin-covered carriers as disclosed in JP-A-62-39879 and JP-A-56-11461
can be used.

[0026] As the specific examples of carriers, the following resin-covered
carriers are exemplified. That is, as the nuclear particles of the
carriers, shaped articles of generally used iron powders, ferrite, and
magnetite are exemplified, and the average particle size thereof is 30
μm to 20 μm or so. As the covering resins of the nuclear particles,
styrenes, e.g., styrene, parachlorostyrene, α-methylstyrene, etc.;
α-methylene fatty acid monocarboxylic acids, e.g., methyl acrylate,
ethyl acrylate, n-propyl acrylate, lauryl acrylate, 2-ethylhexyl
acrylate, methyl methacrylate, n-propyl methacrylate, lauryl
methacrylate, 2-ethylhexyl methacrylate, etc.; nitrogen-containing
acryls, dimethylaminoethyl methacrylate, etc.; vinylnitriles, e.g.,
acrylonitrile, methacrylo-nitrile, etc.; vinylpyridines, e.g.,
2-vinylpyridine, 4-vinylpyridine, etc.; vinyl ethers, e.g., vinyl methyl
ether, vinyl isobutyl ether, etc.; vinyl ketones, e.g., vinyl methyl
ketone, vinyl ethyl ketone, vinyl isopropenyl ketone, etc.; polyolefins,
e.g., ethylene, propylene, etc.; silicones, e.g., methylsilicone,
methylphenylsilicone, etc.; copolymers of a vinyl-based
fluorine-containing monomer, e.g., vinylidene fluoride,
tetrafluoro-ethylene, hexafluoroethylene, etc.; polyesters containing
bisphenol, glycol, or the like; epoxy resins; polyurethane resins;
polyamide resins; cellulose resins; polyether resins, etc., are
exemplified. Especially preferred are resins obtained by polymerization
of a polymeric monomer having an aromatic ring, this is for the reason
that the resins obtained by polymerization of a polymeric monomer having
an aromatic ring are easy to retain static electricity at the aromatic
ring part at charging time of the toner, accordingly even when the ratio
of the non-discoloring release agent particles are increased in the
developer, it is thought that generation of excessive quantity of
electrification of the non-discoloring release agent particles can be
controlled. More preferred resins are resins obtained by polymerization
of a polymeric monomer containing, as a polymeric monomer, styrene whose
aromatic ring part easily comes directly into contact with the toner.
Resins obtained by the polymerization of a polymerizable monomer having
the aromatic rings are preferred. This is for the reason that the
directions of aromatic rings in a row of styrene are liable to a uniform
direction due to steric hindrance and it is easier to retain static
electricity. These resins may be used in one kind alone or in combination
of two or more kinds. The content of the covering resin is 0.1 parts by
mass to 10 parts by mass or so to the carrier, and preferably 0.5 parts
by mass to 3.0 parts by mass. In the manufacture of the carrier, a
heating type kneader, a beating type Henschel mixer, a UM mixer and the
like can be used, and depending upon the amount of the resin to be
covered, it is possible to use a heating type fluidized rolling bed and a
heating type kiln.

[0027] The mixing ratio of the electrostatic image developing toner and
carrier in the electrostatic image developer is not especially restricted
and it can be arbitrarily selected depending upon purpose.

[Image-Forming Apparatus]

[0028] The image-forming apparatus in the exemplary embodiment will be
described in the next place.

[0029]FIG. 1 is a schematic diagram showing the example of the
construction of the image-forming apparatus to form an image according to
the image-forming method in the exemplary embodiment. Image-forming
apparatus 200 shown in FIG. 1 comprises housing 400 in which four
electrophotographic photoreceptors 401a to 401d are arranged mutually in
parallel along intermediate transfer belt 409. With respect to
electrophotographic photoreceptors 401a to 401d, for example, it is
possible for electrophotographic photoreceptor 401a to form a yellow
color image, electrophotographic photoreceptor 401b a magenta color
image, electrophotographic photoreceptor 401c a cyan color image, and
electrophotographic photoreceptor 401d a black color image, respectively.

[0030] It is possible for each of electrophotographic photoreceptors 401a
to 401d to rotate in a predetermined direction (counterclockwise in the
FIGURE), and charging rolls 402a to 402d, developing apparatus 404a to
404d, first transfer rolls 410a to 410d, and cleaning blades 415a to 415d
are arranged in the rotating direction. It is possible to feed the toners
of four colors of black, yellow, magenta and cyan respectively housed in
toner cartridges 405a to 405d to developing apparatus 404a to 404d,
respectively. First transfer rolls 410a to 410d are respectively in
contact with electrophotographic photoreceptors 401a to 401d sandwiching
intermediate transfer belt 409.

[0031] Further, exposure apparatus 403 is arranged at the predetermined
position in housing 400, and it is possible to irradiate the surface of
each of electrophotographic photoreceptors 401a to 401d after being
charged with the light of beam coming out of exposure apparatus 403, by
which each process of charging, exposure, development, first transfer and
cleaning is carried out in sequence in the rotation process of
electrophotographic photoreceptors 401a to 401d, and a toner image of
each color is transferred to intermediate transfer belt 409 to be
superposed.

[0032] Here, charging rolls 402a to 402d are rolls to bring electrically
conductive members (charging rolls) into contact with the surfaces of
electrophotographic photoreceptors 401a to 401d to uniformly apply
voltage to the photoreceptors to charge the photoreceptors to
predetermined electric potential (the charging process). Incidentally,
charging by contact charging system may be performed with a charging
brush, a charging film or a charging tube, besides the charging rolls
shown in the exemplary embodiment. Alternatively, charging may be
performed according to non-contact system with Corotron or Scorotron.

[0033] As exposure apparatus 403, optical system apparatus capable of
desirably imagewise exposing light sources such as a semiconductor laser,
an LED (light emitting diode), a liquid crystal shutter, etc., on the
surfaces of electrophotographic photoreceptors 401a to 401d can be used.
Of these apparatus, by the use of exposure apparatus capable of exposure
of incoherent light, interference fringe between the conductive base
substances and photosensitive layers of electrophotographic
photoreceptors 401a to 401d can be prevented.

[0034] In developing apparatus 404a to 404d, ordinary developing apparatus
performing development by contacting or not contacting any of the
above-described two-component electrostatic image developers (the
developing process) can be used. As such developing apparatus, there is
no restriction so long as the two-component electrostatic image
developers are used, and known apparatus can be arbitrarily selected
depending upon purposes. In the first transfer process, by the
application of first transfer bias of reverse polarity of the toner
carried by the image-holding member to first transfer rolls 410a to 410d,
a toner of each color is first transferred from the image holding member
to intermediate transfer belt 409 in order.

[0035] Cleaning blades 415a to 415d are those to remove remaining toner
adhered on the surface of the electrophotographic photoreceptor after
transfer process, by which the surface-cleaned electrophotographic
photoreceptor is repeatedly offered to the image-forming process. As the
materials of the cleaning blades, urethane rubber, neoprene rubber, and
silicone rubber are exemplified.

[0036] Intermediate transfer belt 409 is supported by driving roll 406,
backup roll 408, and tension roll 407 with the prescribed tension, and is
capable of rotating without causing deflection by the rotation of these
rolls. Further, second transfer roll 413 is arranged so as to come into
contact with backup roll 408 with intermediate transfer belt 409 between.

[0037] By the application of second transfer bias of reverse polarity of
the toner on the intermediate transfer body to second transfer roll 413,
the toner is second transferred from the intermediate transfer belt to a
recording medium. Intermediate transfer belt 409 which passes between
backup roll 408 and second transfer roll 413 is surface-cleaned by
cleaning blade 416 arranged in the vicinity of driving roll 406, or by
the destaticizer (not shown in the FIGURE), and repeatedly offered to the
next image forming process. Further, tray 411 (a transfer-receiving
medium tray) is provided in the predetermined position in housing 400,
and transfer-receiving medium 500 such as paper in tray 411 is
transported between intermediate transfer belt 409 and second transfer
roll 413, and further between two fixing rolls 414 contacting to each
other in sequence by means of transporting rolls 412, and discharged out
of housing 400.

[Image-Forming Method]

[0038] The image-forming method in the exemplary embodiment has at least a
process of charging a latent image-holding member, a process of forming a
latent image on the latent image-holding member, a process of developing
the latent image on the latent image-holding member with the
electrophotographic developer, a first transfer process of transferring
the developed toner image onto an intermediate transfer body, a second
transfer process of transferring the toner image transferred to the
intermediate transfer body to a recording medium, and a process of fixing
the toner image by means of heat and pressure. The developer is a
developer at least containing the electrostatic image developing toner of
the invention. The developer may be either a one-component type or
two-component type developer.

[0039] As each of the above processes, a known process in image-forming
methods can be used.

[0040] As the latent image-holding member, for example, an
electrophotographic photoreceptor and a dielectric recording member can
be used. In the case of the electrophotographic photoreceptor, the
surface of the electrophotographic photoreceptor is uniformly charged
with a Corotron charger or a contact type charger, and then exposed to
form an electrostatic latent image (the latent image-forming process). In
the next place, the latent image is brought into contact with, or in
close vicinity to, a developing roll having formed a developer layer on
the surface thereof, and toner particles are adhered to the electrostatic
latent image to form a toner image on the electrophotographic
photoreceptor (the developing process). The formed toner image is
transferred to the surface of a transfer-receiving material by means of a
Corotron charger and the like (the transfer process). Further, if
necessary, the toner image transferred to the surface of the
transfer-receiving material is thermally fixed by a fixing apparatus to
form a final toner image.

[0041] In the thermal fixing with a fixing apparatus, for preventing
offset and the like, a release agent is fed to a fixing member in an
ordinary fixing apparatus, but it is not necessary to feed a release
agent in the fixing apparatus of the image-forming apparatus in the
exemplary embodiment, and fixing is performed by oil-less fixing.

[0042] A method of feeding a release agent to the surface of a roller or a
belt as the fixing member for use in the thermal fixation is not
especially restricted and, for example, a pad system of using a pad
impregnated with a liquid release agent, a web system, a roller system,
and a non-contact type shower system (a spray system) are exemplified,
and the web system and roller system are preferred of these systems.
These systems are advantageous in that the release agent can be evenly
fed and the feeding amount can be easily controlled. Incidentally, for
the purpose of feeding the release agent evenly to the fixing member
entirely according to the shower system, it is necessary to use a blade
or the like separately.

[0043] As the transfer-receiving material (a recording material) to which
a toner image is transferred, for example, plain paper for use in
electrophotographic copiers and printers, and OHP sheets are exemplified.

[Process Cartridge]

[0044] In the invention, at least one selected from the group consisting
of a latent image holding member, a charging unit for charging the latent
image holding member, an exposing unit for exposing the charged latent
image holding member to form an electrostatic latent image on the latent
image holding member, a developing unit for developing the electrostatic
latent image with the electrostatic image developer according to the
exemplary embodiment to form a toner image, a transfer unit for
transferring the toner image from the latent image holding member to a
transfer-receiving member, and a cleaning unit for removing the toner
remaining on the surface of the latent image holding member may
constitute a process cartridge.

[0045] Further, it is preferred for the process cartridge to include at
least a developing unit.

[0046] The process cartridge is attachable to and detachable from the
image-forming apparatus main body, and constitutes the image-forming
apparatus together with the image-forming apparatus main body.

[Toner Cartridge]

[0047] In the next place, a toner cartridge according the exemplary
embodiment will be described below. The toner cartridge according to the
exemplary embodiment is attachable to and detachable from the
image-forming apparatus, and in the toner cartridge for housing a toner
to be supplied to the developing unit provided in the image-forming
apparatus, the toner is at least the toner according to the exemplary
embodiment. Further, it is sufficient for the toner cartridge according
to the exemplary embodiment to contain at least a toner and, for example,
a developer may be housed depending upon the mechanism of the
image-forming apparatus.

[0048] Accordingly, in the image-forming apparatus wherein the toner
cartridge has constitution of being attachable and detachable, the toner
according to the exemplary embodiment is easily supplied to the
image-forming apparatus by the use of the toner cartridge housing the
toner according to the exemplary embodiment.

Example

[0049] The invention will be described with reference to examples, but the
invention is by no means restricted thereto. In the examples, "parts"
means "parts by mass" and "%" means "% by mass" unless otherwise
indicated.

[0050] In the examples, each measurement is performed as follows.

(Measuring Methods of Particle Size and Particle Size Distribution)

[0051] Measurements of particle size and particle size distribution are
described below.

[0052] When the particle sizes to be measured are 2 μm or more, Coulter
Multisizer II type (manufactured by Beckman Coulter, Inc.) is used as the
apparatus to measure the particle sizes and ISOTON-II (manufactured by
Beckman Coulter, Inc.) is used as the electrolyte.

[0053] As the measuring method, 0.5 mg to 50 mg of a measuring sample is
put in 2 mL of a 5% aqueous solution containing a surfactant as a
dispersant, preferably sodium alkylbenzenesulfonate. This is poured into
100 mL of the electrolyte.

[0054] The electrolyte in which the sample is suspended is subjected to
dispersion treatment with an ultrasonic disperser for about 1 minute. The
particle size distribution, of particles having the particle size of 2
μm to 60 μm is measured with Coulter Multisizer II type by using
the aperture of diameter of 100 μm, from which the volume average
particle size distribution and number average particle size distribution
are found. The number of measured particles is 50,000.

[0055] Particle size distribution of a toner is measured as follows. The
measured particle size distribution data are plotted relative to the
divided particle size ranges (channels) to draw the volume cumulative
distribution from the particles having a smaller particle size, and the
cumulative volume particle size giving accumulation of 16% is defined as
D16v, the cumulative volume particle size giving accumulation of 50%
is defined as D50v, and the cumulative volume particle size giving
accumulation of 84% is defined as D84v.

[0056] The volume average particle size in the invention is D50v and
the volume average particle size index GSDv is computed according to
the following equation.

GSDv=[(D84v)/(D16v)]0.5

[0057] When the particle sizes to be measured are less than 2 μm, a
laser diffraction system particle size distribution measuring instrument
(LA-700, manufactured by Horiba, Ltd.) is used as the apparatus to
measure the particle sizes. As measuring method, the sample in a state of
dispersion is adjusted to be about 2 g in a solid state, and ion exchange
water is added thereto to make about 40 mL. The resulting sample is
poured into a cell to get appropriate concentration, stands still for
about 2 minutes, and particle sizes are measured when the concentration
in the cell is almost stabilized. The volume average particle size of the
obtained every channel is accumulated from the small size side of the
volume average particle size and particle sizes giving accumulation of
50% are taken as the volume average particle size.

[0058] When powder such as an external additive is measured, 2 g of a
measuring sample is put in 50 mL of a 5% aqueous solution of a
surfactant, preferably sodium alkylbenzenesulfonate, which is dispersed
with an ultrasonic disperser (1,000 Hz) for 2 minutes to prepare a
sample, and measuring is performed in the same manner as in the
measurement of the foregoing dispersion.

(Measuring Method of Glass Transition Temperature)

[0059] The glass transition temperature of the toner is determined
according to a DSC (differential scanning calorimeter) measuring method
and found from the subject maximum peak measured in conformity with ASTM
D3418-8.

[0060] In the measurement of the subject maximum peak, DSC-7 (manufactured
by Perkin Elmer, Inc.) can be used. The melting temperatures of indium
and zinc are used for temperature correction of the detecting part of the
apparatus, and heat of fusion of indium is utilized for calorimetric
correction. An aluminum pan is used as the sample, and an empty pan is
set for reference and measurement is performed at a temperature rising
rate of 10° C./min.

[0063] A toner (1.0 g) is dissolved in sulfuric acid to make 50 mL of a
constant volume. One (1) mL of the solution is fractioned, and 4 mL of
hexane and the known amount of cleanup spike are added thereto for
liquid-Liquid extraction, and a hexane layer is fractioned. This
operation is repeated two times, and the obtained hexane layer is
concentrated to about 1 mL and then cleaned-up by using silica gel
cartridge (Supelclean LC-Si, 6 mL Glass Tube, 1 g, manufactured by
Supelco Inc.). After concentrating 10 mL of the obtained hexane eluate,
standard material in syringe spike is added to make 50 μL, which is
the analytical test solution, and the content is determined by the
calibration curve.

[0064] The invention will be described with reference to more specific
examples and comparative examples, but the invention is by no means
restricted thereto. In the following description, "parts" means "parts by
mass" unless otherwise indicated.

Manufacture of Pigment 1:

[0065] One (1) part of Pigment Green 7 (manufactured by BASF Japan Ltd.)
is dispersed in 100 parts of acetone and stirred for 1 hour, and then the
dispersion is filtered. This process is repeated three times and then the
reaction product is dried to obtain Pigment 1.

Manufacture of Pigment 2:

[0066] One-hundred (100) parts of a mixed solvent of
tetrahydrofuran/toluene (1/1) is added to 1 part of Pigment 1, the
solution is stirred for 1 hour and then filtered. This process is
repeated two times and then the reaction product is dried to obtain
Pigment 2.

Manufacture of Pigment 3:

[0067] One-hundred (100) parts of a mixed solvent of
tetrahydrofuran/toluene (1/1) is added to 1 part of Pigment 2, the
solution is stirred for 1 hour with an ultrasonic disperser (GSD1200AT,
manufactured by Sonic Technology, Inc.) at maximum output, and then
filtered and dried to obtain Pigment 3.

Manufacture of Pigment 4:

[0068] Dispersing condition used in the manufacture of Pigment 3 is
repeated with Pigment 3 to obtain Pigment 4.

Manufacture of Pigment 5:

[0069] One-hundred (100) parts of a mixed solvent of
tetrahydrofuran/totuene (1/1) is added to 1 part of Pigment 2, the
solution is stirred for 1 hour with the ultrasonic disperser used in the
manufacture of Pigment 3 at maximum output, and then Soxhlet extraction
is performed for 2 hours. After filtration of the reaction product, 100
parts of tetrahydrofuran is added thereto, and then the solution is
stirred for 1 hour, filtered, and dried to obtain Pigment 5.

Manufacture of Pigment 6:

[0070] Pigment 6 is manufactured in the same manner as in the manufacture
of Pigment 5 except for changing Soxhlet extraction to 24 hours,

Manufacture of Pigment 7:

[0071] Pigment 7 is manufactured in the same manner as in the manufacture
of Pigment 5 except for changing Soxhlet extraction to 30 hours.

Manufacture of Pigment 8:

[0072] Pigment 8 is manufactured in the same manner as in the manufacture
of Pigment 4 except for changing the pigment from Pigment Green 7 to
Pigment Green 36 (manufactured by BASF Japan Ltd.).

Manufacture of Pigment 9:

[0073] Pigment 9 is manufactured in the same manner as in the manufacture
of Pigment 4 except for changing the pigment from Pigment Green 7 to
Pigment Orange 61 (manufactured by Ciba Geigy Corp.).

[0075] The above mixture is thermally kneaded with an extruder, and after
cooling, the kneaded product is coarsely pulverized, finely pulverized,
and classified to obtain toner mother particles of D50=7.0 μm.

[0076] Toner A is manufactured by mixing 100 parts by mass of the toner
mother particles and 0.7 parts by mass of dimethyl silicone oil-treated
silica particles (trade name: RY200, average particle size: 12 nm,
manufactured by Nippon Aerosil Co., Ltd.) with a Henschel mixer. The
content of all the chlorine-substituted benzene derivatives in Toner A is
1.0 ppb.

Manufacturing Method of Toner B:

[0077] Toner B is obtained according to the manufacturing method of Toner
A except for changing Pigment 4 to Pigment 3. The content of all the
chlorine-substituted benzene derivatives in Toner B is 3.0 ppb.

Manufacturing Method of Toner C:

[0078] Toner C is obtained according to the manufacturing method of Toner
A except for changing Pigment 4 to Pigment 2. The content of all the
chlorine-substituted benzene derivatives in Toner C is 10.0 ppb.

Manufacturing Method of Toner D:

[0079] Toner D is obtained according to the manufacturing method of Toner
A except for changing Pigment 4 to Pigment 5. The content of all the
chlorine-substituted benzene derivatives in Toner D is 0.1 ppb.

Manufacturing Method of Toner E:

[0080] Toner E is obtained according to the manufacturing method of Toner
A except for changing Pigment 4 to Pigment 6. The content of all the
chlorine-substituted benzene derivatives in Toner E is 0.01 ppb,

[0082] A flask having a capacity of 5 liters and equipped with a stirrer,
a nitrogen-introducing tube, a temperature sensor, and a distillation
column is charged with a monomer having the above composition ratio. The
temperature of the flask is increased to 190° C. over 1 hour, and
after confirming that the reaction system is stirred without dispersion,
when the total amount of three components described above is taken as 100
parts by mass, 1.0% by mass of titaniumtetraethoxide is charged relative
to 100 parts by mass of the total component of the three components.
Further, the temperature of the reaction system is increased to
240° C. over 6 hours while the produced water is distilled off and
then the dehydrative condensation reaction is continued for 2.5 hours at
240° C. to obtain an amorphous polyester resin (a) having a glass
transition point of 63° C. and a weight average molecular weight
(Mw) of 17,000.

[0084] The above composition is subjected to powder mixing with a Henschel
mixer and thermal kneading in an extruder at a prescribed temperature of
100° C., and after cooling, the kneaded product is coarsely
pulverized, finely pulverized, and classified to obtain toner mother
particles having a volume average particle size D50 of 82 μm.

[0085] Toner F is manufactured by mixing 100 parts by mass of the toner
mother particles and 0.7 parts by mass of dimethyl silicone oil-treated
silica particles (trade name: RY200, manufactured by Nippon Aerosil Co.,
Ltd.) with a Henschel mixer. The content of all the chlorine-substituted
benzene derivatives in Toner F is 1.0 ppb.

[0087] The above composition is subjected to powder mixing with a Henschel
mixer and thermal kneading in an extruder at a prescribed temperature of
100° C., and after cooling, the kneaded product is coarsely
pulverized, finely pulverized, and classified to obtain toner mother
particles having a volume average particle size D50 of 8.2 μm.

[0088] Toner G is manufactured by mixing 100 parts by mass of the toner
mother particles and 0.7 parts by mass of dimethyl silicone oil-treated
silica particles (trade name: RY200, manufactured by Nippon Aerosil Co.,
Ltd.) with a Henschel mixer. The content of all the chlorine-substituted
benzene derivatives in Toner G is 1.0 ppb.

[0090] The above composition is subjected to powder mixing with a Henschel
mixer and thermal kneading in an extruder at a prescribed temperature of
100° C., and after cooling, the kneaded product is coarsely
pulverized, finely pulverized, and classified to obtain toner mother
particles having a volume average particle size D50 of 8.2 μm.

[0091] Toner H is manufactured by mixing 100 parts by mass of the toner
mother particles and 0.7 parts by mass of dimethyl silicone oil-treated
silica particles (trade name; RY200, manufactured by Nippon Aerosil Co.,
Ltd.) with a Henschel mixer. The content of all the chlorine-substituted
benzene derivatives in Toner H is 1.0 ppb.

[0093] The above mixture is thermally kneaded with an extruder, and after
cooling, the kneaded product is coarsely pulverized, finely pulverized,
and classified to obtain toner mother particles of D50=5.0 μm.

[0094] Toner I is manufactured by mixing 100 parts by mass of the toner
mother particles and 0.7 parts by mass of dimethyl silicone oil-treated
silica particles (trade name: RY200, manufactured by Nippon Aerosil Co.,
Ltd.) with a Henschel mixer. The content of all the chlorine-substituted
benzene derivatives in Toner I is 1.0 ppb.

Manufacturing Method of Toner J:

[0095] Toner J is obtained according to the manufacturing method of Toner
I except for not blending all the chlorine-substituted benzene
derivatives. The content of all the chlorine-substituted benzene
derivatives in Toner J is 0 ppb.

Manufacturing Method of Toner K:

[0096] Toner K is obtained according to the manufacturing method of Toner
A except for changing Pigment 4 to Pigment 7. The content of all the
chlorine-substituted benzene derivatives in Toner K is 0.008 ppb.

Manufacturing Method of Toner L:

[0097] Toner L is obtained according to the manufacturing method of Toner
A except for changing Pigment 4 to Pigment 1. The content of all the
chlorine-substituted benzene derivatives in Toner L is 50 ppb.

Manufacture of Developers:

[0098] Developers A to L having toner concentration of 7% by weight are
manufactured by mixing each of Toner A to Toner L and ferrite carrier
covered with a resin (PMMA having Mw of 70,000).

Methods of Evaluations:

(Evaluation of Antibacterial Action of Image)

<Specimen>

[0099] By using each of the above prepared developers, a solid image
having an area of 10 cm2 of image area factor of 100% is formed on
an image-receiving medium by the use of general non-coat full color
special paper as the image-receiving medium on condition of 25°
C., 50% RH by means of modified DocuPrint C1616 (manufactured by Fuji
Xerox Co., Ltd.). As the specimen, 10 sheets of paper each cut out in a
size of 50 mm×50 mm so that the image-fixing area positions in the
center are prepared.

<Test Method>

[0100] With the above-formed image as specimen, viable bacterial number at
35° C. after 24 hours by film adhesion method is evaluated. As the
test bacteria, coli bacilli (ISO3301) are used. For the preparation of
test bacterium solution, a general bouillon culture medium is prepared by
dissolving 5 mg of meat extract, 10 mg of peptone, and 5 mg of sodium
chloride in 1 liter of distilled water. In the next place, a solution is
prepared by diluting the above bouillon culture medium with distilled
water to 1/500, and coli bacilli are suspended in the solution so that
the number of coli bacilli reaches 106 per 1 mL.

[0101] Onto the specimen is dripped 0.5 mL of bacterium solution and a
polyethylene film is adhered thereto, which is allowed to stand at
35° C. for 24 hours. The coli bacilli adhered to the specimen and
the covered film are thoroughly rinsed out into a sterilized Petri dish
with 9.5 mL of SCDLP culture medium (manufactured by Nippon Seiyaku Co.,
Ltd.). The viable bacterial number in 1 mL of the rinsed water is
measured by an agar plate dilution method with a standard agar medium for
measurement of the number of bacteria (manufactured by Nissui
Pharmaceutical Co., Ltd.), from which the rate of sterilization is
computed. The rate of sterilization is computed as the ratio of the
viable bacterial number after elapse of 24 hours to the viable bacterial
number at the beginning time of the test, and the average value of 10
sheets of paper is found and evaluated according to the following
criteria. The tolerance is up to grade C.

A: Sterilization rate is 99.9% or more. B: Sterilization rate is 98% or
more and less than 99.9%. C: Sterilization rate is 97% or more and less
than 98%. D: Sterilization rate is less than 97%.

(Evaluation of Unevenness of Antibacterial Action of Image)

[0102] The difference between the values of the least upper bound and the
greatest lower bound of the rates of sterilization of 10 sheets is taken
as unevenness and evaluated according to the following criteria.

A: Unevenness of sterilization rate is less than 0.5%. B: Unevenness of
sterilization rate is 0.5% or more and less than 1.0%. C: Unevenness of
sterilization rate is 1.0% or more and less than 2.0%. D: Unevenness of
sterilization rate is 2.0% or more.

(Evaluation of Toner Reproducibility Under High Temperature High Humidity)

[0103] By using each of the above prepared developers, a solid image
having an area of 10 cm2 of image area factor of 100% and an image
having an area of 10 cm2 of image area factor of 50% are formed on
an image-receiving medium by the use of general non-coat full color
special paper as the image-receiving medium on condition of 30°
C., 90% RH by means of modified DocuPrint C1616 (manufactured by Fuji
Xerox Co., Ltd.). The difference between the concentrations of the image
having an image area factor of 100% and the image having an image area
factor of 50% measured with X-rite 938 is taken as toner reproducibility
and evaluated according to the following criteria.

A: Toner reproducibility is less than 0.90. B: Toner reproducibility is
0.90 or more and less than 0.95. C: Toner reproducibility is 0.95 or more
and less than 1.00. D: Toner reproducibility is 1.00 or more.